Properties of the Number -6981

Nine Hundred Eighty-One

Basics

Value: -6982 → -6981 → -6980

Parity: odd

Prime: No

Previous Prime:

Next Prime: 1

Digit Sum: 24

Digital Root: 6

Palindrome: No

Factorization: 3 × 13 × 179

Divisors: 1, 3, 13, 39, 179, 537, 2327, 6981

Polygonal

Triangular: No

Square: No

Pentagonal: No

Hexagonal: No

Heptagonal: No

Tetrahedral: No

Today's Target

5184 Try Today's Challenge

Representations

Binary: -1101101000101

Octal: -15505

Duodecimal: -4059

Hexadecimal: -1b45

Square: 48734361

Square Root: 83.55237878121723

Classification

Fibonacci: No

Bell Number: No

Factorial Number: No

Regular Number: No

Perfect Number: No

Special

Kaprekar Constant: No

Munchausen Constant: No

Armstrong Number: No

Kaprekar Number: No

Catalan Number: No

Vampire Number: No

Taxicab Number: No

Super Prime: No

Friedman Number: No

Fermat Number: No

Cullen Number: No

OEIS Sequences

Take the first n numbers written in base 4, concatenate them, then convert from base 4 to base 10. A48436

Second 11-gonal (or hendecagonal) numbers: a(n) = n*(9·n+7)/2. A62728

Numbers k such that L(2·k + 1) is prime, where L(m) is a Lucas number. A117522

Number of distinct means of nonempty subsets of {1,...,n}. A135342

T(n,k)=Number of nXk arrays of the minimum value of corresponding elements and their horizontal, diagonal or antidiagonal neighbors in a random 0..2 nXk array. A219128

a(1)=0, and a(n+1) is the position of first occurrence of a(n) in the decimal expansion of 1/π. A98319

Square array, read by antidiagonals, where row n equals the crystal ball sequence for D_n lattice. A108553

Least number k such that n concatenated with k produces a cube. A245631

Column 2 of triangle A128545; a(n) is the coefficient of q²ⁿ⁺⁴ in the central q-binomial coefficient [2n+4,n+2]. A128552

a(n) = 2/n²*( ∑_k=0..n-1 (2·k+1)*C(n-1,k)²*C(n+k,k) ), where C(m,k) denotes the binomial coefficient m!/(k!*(m-k)!). A246542